1 files changed, 106 insertions, 0 deletions
diff --git a/webrtc/test/layer_filtering_transport.cc b/webrtc/test/layer_filtering_transport.cc
new file mode 100644
index 0000000000..a4ebf47f93
--- /dev/null
+++ b/webrtc/test/layer_filtering_transport.cc
@@ -0,0 +1,106 @@
+/*
+ *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/base/checks.h"
+#include "webrtc/modules/rtp_rtcp/interface/rtp_header_parser.h"
+#include "webrtc/modules/rtp_rtcp/interface/rtp_rtcp_defines.h"
+#include "webrtc/modules/rtp_rtcp/source/byte_io.h"
+#include "webrtc/modules/rtp_rtcp/source/rtp_format.h"
+#include "webrtc/modules/rtp_rtcp/source/rtp_utility.h"
+#include "webrtc/test/layer_filtering_transport.h"
+
+namespace webrtc {
+namespace test {
+
+LayerFilteringTransport::LayerFilteringTransport(
+    const FakeNetworkPipe::Config& config,
+    Call* send_call,
+    uint8_t vp8_video_payload_type,
+    uint8_t vp9_video_payload_type,
+    uint8_t tl_discard_threshold,
+    uint8_t sl_discard_threshold)
+    : test::DirectTransport(config, send_call),
+      vp8_video_payload_type_(vp8_video_payload_type),
+      vp9_video_payload_type_(vp9_video_payload_type),
+      tl_discard_threshold_(tl_discard_threshold),
+      sl_discard_threshold_(sl_discard_threshold) {}
+
+uint16_t LayerFilteringTransport::NextSequenceNumber(uint32_t ssrc) {
+  auto it = current_seq_nums_.find(ssrc);
+  if (it == current_seq_nums_.end())
+    return current_seq_nums_[ssrc] = 10000;
+  return ++it->second;
+}
+
+bool LayerFilteringTransport::SendRtp(const uint8_t* packet,
+                                      size_t length,
+                                      const PacketOptions& options) {
+  if (tl_discard_threshold_ == 0 && sl_discard_threshold_ == 0) {
+    // Nothing to change, forward the packet immediately.
+    return test::DirectTransport::SendRtp(packet, length, options);
+  }
+
+  bool set_marker_bit = false;
+  rtc::scoped_ptr<RtpHeaderParser> parser(RtpHeaderParser::Create());
+  RTPHeader header;
+  parser->Parse(packet, length, &header);
+
+  if (header.payloadType == vp8_video_payload_type_ ||
+      header.payloadType == vp9_video_payload_type_) {
+    const uint8_t* payload = packet + header.headerLength;
+    RTC_DCHECK_GT(length, header.headerLength);
+    const size_t payload_length = length - header.headerLength;
+    RTC_DCHECK_GT(payload_length, header.paddingLength);
+    const size_t payload_data_length = payload_length - header.paddingLength;
+
+    const bool is_vp8 = header.payloadType == vp8_video_payload_type_;
+    rtc::scoped_ptr<RtpDepacketizer> depacketizer(
+        RtpDepacketizer::Create(is_vp8 ? kRtpVideoVp8 : kRtpVideoVp9));
+    RtpDepacketizer::ParsedPayload parsed_payload;
+    if (depacketizer->Parse(&parsed_payload, payload, payload_data_length)) {
+      const uint8_t temporalIdx =
+          is_vp8 ? parsed_payload.type.Video.codecHeader.VP8.temporalIdx
+                 : parsed_payload.type.Video.codecHeader.VP9.temporal_idx;
+      const uint8_t spatialIdx =
+          is_vp8 ? kNoSpatialIdx
+                 : parsed_payload.type.Video.codecHeader.VP9.spatial_idx;
+      if (sl_discard_threshold_ > 0 &&
+          spatialIdx == sl_discard_threshold_ - 1 &&
+          parsed_payload.type.Video.codecHeader.VP9.end_of_frame) {
+        // This layer is now the last in the superframe.
+        set_marker_bit = true;
+      }
+      if ((tl_discard_threshold_ > 0 && temporalIdx != kNoTemporalIdx &&
+           temporalIdx >= tl_discard_threshold_) ||
+          (sl_discard_threshold_ > 0 && spatialIdx != kNoSpatialIdx &&
+           spatialIdx >= sl_discard_threshold_)) {
+        return true;  // Discard the packet.
+      }
+    } else {
+      RTC_NOTREACHED() << "Parse error";
+    }
+  }
+
+  uint8_t temp_buffer[IP_PACKET_SIZE];
+  memcpy(temp_buffer, packet, length);
+
+  // We are discarding some of the packets (specifically, whole layers), so
+  // make sure the marker bit is set properly, and that sequence numbers are
+  // continuous.
+  if (set_marker_bit)
+    temp_buffer[1] |= kRtpMarkerBitMask;
+
+  uint16_t seq_num = NextSequenceNumber(header.ssrc);
+  ByteWriter<uint16_t>::WriteBigEndian(&temp_buffer[2], seq_num);
+  return test::DirectTransport::SendRtp(temp_buffer, length, options);
+}
+
+}  // namespace test
+}  // namespace webrtc